Luminescent coating for electric lamps



Oct. 20, 1942,. G. E. HOLMAN LUMINESCENT COATING FOR ELETRIC LAMPS Filed Ooit. 26, 1940 Gearjre v17 Hobnan 1N VENTOR.

. weight of luminescent material and a ilnal layer of luminescent material.

2. A coating on the inner walls of an electric gaseous discharge lamp comprising: a primary layer of a material capable of transmitting the wavelengths of light Acorresponding to a desired 10 pre-mixed and separately joined layer compriscolor and capable also of absorbing all other wavelengths; an intermediate layer comprising a mixture of substantially equal parts by weight of said primary layer material and a luminescent layer material; and a final layer of said luminescent material capable of emitting, among i5 other wavelengths of light, the wavelength corresponding to the desired color.

3. A coating of the character described, said coating including: a layer comprising light illtering material only, on the inner walls of an electric gaseous discharge lamp; a layer comprising luminescent material only, within said lamp and overlying said layer of light ltering material, and a binding agent in the form of a ing a mixture of light filtering material and luminescent material, said binding layer lying between and joining said lter layer and said luminescent layer.

GEORGE E. HOLMAN. 

